1. Field of Invention
The present invention relates to apparatuses and methods for monitoring, measuring, or analyzing the lubricity of fluid samples in conjunction with solid samples.
2. Description of Prior Art
U.S. Pat. No. 6,105,415 describes a method and apparatus for testing the lubricity of a drilling mud. The test is accomplished by rotating a core sample so that it rubs against a metal surface (simulating a rotating pipe or drill string in a well) and then saturating the core sample and the metal surface with a drilling mud. The energy required to rotate the core sample while it is saturated with the drilling mud is determined and this measurement is used to determine the lubricity of the drilling mud. This design is specifically intended to simulate downhole conditions, and requires both a drilling fluid sample and a core sample, with the core sample being positioned at only one angle. This limits the test parameters that can be specified to a relatively narrow range.
U.S. Pat. No. 3,060,721 describes an apparatus for testing lubricants by measuring the change in electrical resistance provided by wear or attrition of a test specimen. The apparatus of this invention provides an eccentric rotating surface and means for supporting a strip-like test specimen so that at least a portion of the periphery of said eccentric rotating surface bears against and rubs the test specimen, and induces cyclic tensile stresses therein. The test specimen and rotating surface are enclosed in a suitable vessel which is provided with inlet and outlet means, such that a controlled corrosive environment can be caused to exist within the vessel. Means are provided for continuously applying lubricant to the contact surface between the strap-like test specimen and the rotating surface. This apparatus does not, however, provide the means to measure lubricity. The user must employ microscopic measurement to examine the specimen in order to determine the amount of wear, the results of which determination can in turn can be used to calculate the lubricity of a tested fluid. Alternatively, the user may employ an electrical resistance test on the abraded surface of the specimen, should the specimen be made of conductive metal. The test procedures required to use this invention as intended are time-consuming and onerous, and this substantially limits the scope and usefulness of the invention.
U.S. Pat. No. 3,913,377 describes a friction testing machine in which fluids may be tested for lubricity. A disc, rotated continuously by a variable-speed driving means, has friction members clamped against its opposite faces by means of a calibrated, adjustable mechanism which controls the “normal” force holding the members against the disc. The friction force between the members and the disc may be determined by measuring the tangential force produced on the members as the disc rotates. One edge of the disc dips into a bath of the lubricant being tested, to provide lubricant at the juxtaposed disc and member surfaces. A heating means may be provided for the bath, to enable testing at elevated temperatures. While again limiting the testing apparatus to operating only at one angle, this device limits the possible specimen types which might make up the disk to only those which are of a sufficiently solid consistency.
It is an object of this invention to create a device which can measure the lubricity of a fluid submerging two solid samples of various kinds. At least one of the solid samples could be a porous media, and the filtration of said fluid through said porous media could also be measured under varying and controllable conditions, including but not limited to those of temperature and pressure.